@article{aichholzer2014,
  title = {How Has {{Radical Right Support Transformed Established Political Conflicts}}? {{The Case}} of {{Austria}}},
  shorttitle = {How Has {{Radical Right Support Transformed Established Political Conflicts}}?},
  author = {Aichholzer, Julian and Kritzinger, Sylvia and Wagner, Markus and Zeglovits, Eva},
  date = {2014-01-02},
  journaltitle = {West European Politics},
  shortjournal = {West European Politics},
  volume = {37},
  number = {1},
  pages = {113--137},
  issn = {0140-2382, 1743-9655},
  doi = {10.1080/01402382.2013.814956},
  url = {http://www.tandfonline.com/doi/full/10.1080/01402382.2013.814956},
  urldate = {2024-10-10},
  langid = {english}
}

@article{brambor2006,
  title = {Understanding Interaction Models: {{Improving}} Empirical Analyses},
  shorttitle = {Understanding Interaction Models},
  author = {Brambor, Thomas and Clark, William Roberts and Golder, Matt},
  date = {2006},
  journaltitle = {Political analysis},
  volume = {14},
  number = {1},
  pages = {63--82},
  publisher = {Cambridge University Press},
  url = {https://www.cambridge.org/core/journals/political-analysis/article/understanding-interaction-models-improving-empirical-analyses/9BA57B3720A303C61EBEC6DDFA40744B},
  urldate = {2024-10-24}
}

@article{castanhosilva2020,
  title = {An {{Empirical Comparison}} of {{Seven Populist Attitudes Scales}}},
  author = {Castanho Silva, Bruno and Jungkunz, Sebastian and Helbling, Marc and Littvay, Levente},
  date = {2020-06},
  journaltitle = {Political Research Quarterly},
  shortjournal = {Political Research Quarterly},
  volume = {73},
  number = {2},
  pages = {409--424},
  issn = {1065-9129, 1938-274X},
  doi = {10.1177/1065912919833176},
  url = {https://journals.sagepub.com/doi/10.1177/1065912919833176},
  urldate = {2024-10-10},
  abstract = {With the recent upsurge of populism in developed and transition democracies, researchers have started measuring it as an attitude. Several scales have been proposed for this purpose. However, there is little direct comparison between the available alternatives. Scholars who wish to measure populist attitudes have little information available to help select the best scale for their purposes. In this article, we directly compare seven populist attitudes scales from multiple perspectives: conceptual development, questionnaire design, dimensionality, information, cross-national validity, and external validity. We use original survey data collected online from nine countries in Europe and the Americas, with around 250 participants per country, in which all seven batteries of questions were present. Results show that most scales have important methodological and validity limitations in at least one of the dimensions tested, and should not be used for cross-national comparative research. We recommend populist attitudes items that work better at capturing populism, and more generally provide guidelines for researchers who want to compare different scales that supposedly measure the same construct.},
  langid = {english}
}

@book{deayala2013,
  title = {The Theory and Practice of Item Response Theory},
  author = {De Ayala, Rafael Jaime},
  date = {2013},
  publisher = {Guilford Publications},
  url = {https://books.google.nl/books?hl=nl&lr=&id=NchXAQAAQBAJ&oi=fnd&pg=PP1&dq=De+Ayala,+R.+J.+(2009).+The+Theory+and+Practice+of+Item+Response+Theory.+Guilford+Press.&ots=Xg9LAJZHIy&sig=hcsvE3aBGALZ1e_ohaJuyZQwjok},
  urldate = {2025-06-22}
}

@article{hawkins2009,
  title = {Is {{Chávez Populist}}?: {{Measuring Populist Discourse}} in {{Comparative Perspective}}},
  shorttitle = {Is {{Chávez Populist}}?},
  author = {Hawkins, Kirk A.},
  date = {2009-08},
  journaltitle = {Comparative Political Studies},
  shortjournal = {Comparative Political Studies},
  volume = {42},
  number = {8},
  pages = {1040--1067},
  issn = {0010-4140, 1552-3829},
  doi = {10.1177/0010414009331721},
  url = {https://journals.sagepub.com/doi/10.1177/0010414009331721},
  urldate = {2025-06-29},
  abstract = {This article pushes forward our understanding of populism by developing one of the more underappreciated definitions of populism, populism as discourse. It does so by creating a quantitative measure of populist discourse suitable for cross-country and historical analysis. The article starts by laying out the discursive definition of populism in the context of existing definitions. It then operationalizes this definition through a holistic grading of speeches by current chief executives and a few historical figures. The result is a data set of elite-level populist discourse in more than 40 current and past governments from a variety of countries across the world, with special focus on Latin America. This measurement has high reliability comparable to standard human-coded content analysis, compares well to common understandings of actual cases of populism, and is a reasonably efficient technique even in small samples.},
  langid = {english}
}

@incollection{hawkins2018,
  title = {Textual Analysis: {{Big}} Data Approaches},
  shorttitle = {Textual Analysis},
  booktitle = {The Ideational Approach to Populism},
  author = {Hawkins, Kirk A. and Silva, Bruno Castanho},
  date = {2018},
  pages = {27--48},
  publisher = {Routledge},
  url = {https://www.taylorfrancis.com/chapters/edit/10.4324/9781315196923-2/textual-analysis-kirk-hawkins-bruno-castanho-silva},
  urldate = {2025-06-29}
}

@article{hu1999,
  title = {Cutoff Criteria for Fit Indexes in Covariance Structure Analysis: {{Conventional}} Criteria versus New Alternatives},
  shorttitle = {Cutoff Criteria for Fit Indexes in Covariance Structure Analysis},
  author = {Hu, Li‐tze and Bentler, Peter M.},
  date = {1999-01},
  journaltitle = {Structural Equation Modeling: A Multidisciplinary Journal},
  shortjournal = {Structural Equation Modeling: A Multidisciplinary Journal},
  volume = {6},
  number = {1},
  pages = {1--55},
  issn = {1070-5511, 1532-8007},
  doi = {10.1080/10705519909540118},
  url = {http://www.tandfonline.com/doi/abs/10.1080/10705519909540118},
  urldate = {2024-10-03},
  langid = {english}
}

@article{huber2017,
  title = {On the Distinct Effects of Left-Wing and Right-Wing Populism on Democratic Quality},
  author = {Huber, Robert A. and Schimpf, Christian H.},
  date = {2017},
  journaltitle = {Politics and governance},
  volume = {5},
  number = {4},
  pages = {146--165},
  url = {https://www.cogitatiopress.com/politicsandgovernance/article/view/919},
  urldate = {2024-09-10}
}

@article{huber2020,
  ids = {Huber.2020},
  title = {The Role of Populist Attitudes in Explaining Climate Change Skepticism and Support for Environmental Protection},
  author = {Huber, Robert A.},
  date = {2020-09-18},
  journaltitle = {Environmental Politics},
  shortjournal = {EP},
  volume = {29},
  number = {6},
  pages = {959--982},
  issn = {0964-4016, 1743-8934},
  doi = {10.1080/09644016.2019.1708186},
  url = {https://www.tandfonline.com/doi/full/10.1080/09644016.2019.1708186},
  urldate = {2020-08-18},
  langid = {english}
}

@article{huber2023,
  title = {Populist Parties and the Two‐dimensional Policy Space},
  author = {Huber, Robert A. and Jankowski, Michael and Juen, Christina‐Marie},
  date = {2023-08},
  journaltitle = {European Journal of Political Research},
  shortjournal = {European J Political Res},
  volume = {62},
  number = {3},
  pages = {989--1004},
  issn = {0304-4130, 1475-6765},
  doi = {10.1111/1475-6765.12569},
  url = {https://ejpr.onlinelibrary.wiley.com/doi/10.1111/1475-6765.12569},
  urldate = {2024-08-28},
  abstract = {Abstract             How are parties' ideological positions and levels of populism connected? Existing research either advocates for a U‐shaped relationship between parties' left‐right position and their degree of populism or uses specific dimensions of a two‐dimensional policy space to describe right‐wing populist parties. We provide an integrated perspective to describe parties' degree of populism by arguing that populism is higher when parties put strong emphasis on a collectivist host ideology. This has implications on how these ideologies relate to the two‐dimensional policy space. Combined with salience of policy dimensions, such a perspective allows for a better understanding of the occurrence of populism among right‐ and left‐wing populist parties. Using expert survey data on parties in Europe, we find strong and robust empirical support for the expected~patterns.},
  langid = {english}
}

@article{licht2025,
  title = {Measuring and {{Understanding Parties}}’ {{Anti-elite Strategies}}},
  author = {Licht, Hauke and Abou-Chadi, Tarik and Barberá, Pablo and Hua, Whitney},
  date = {2025-01-01},
  journaltitle = {The Journal of Politics},
  shortjournal = {The Journal of Politics},
  volume = {87},
  number = {1},
  pages = {275--290},
  issn = {0022-3816, 1468-2508},
  doi = {10.1086/730711},
  url = {https://www.journals.uchicago.edu/doi/10.1086/730711},
  urldate = {2025-06-29},
  langid = {english}
}

@article{meguid2005,
  title = {Competition between Unequals: {{The}} Role of Mainstream Party Strategy in Niche Party Success},
  shorttitle = {Competition between Unequals},
  author = {Meguid, Bonnie M.},
  date = {2005},
  journaltitle = {American political science review},
  volume = {99},
  number = {3},
  pages = {347--359},
  publisher = {Cambridge University Press},
  url = {https://www.cambridge.org/core/journals/american-political-science-review/article/competition-between-unequals-the-role-of-mainstream-party-strategy-in-niche-party-success/74958063576E765C21430A8CB57DCC1B},
  urldate = {2024-10-10}
}

@article{meijers2021,
  title = {Measuring {{Populism}} in {{Political Parties}}: {{Appraisal}} of a {{New Approach}}},
  shorttitle = {Measuring {{Populism}} in {{Political Parties}}},
  author = {Meijers, Maurits J. and Zaslove, Andrej},
  date = {2021-02},
  journaltitle = {Comparative Political Studies},
  shortjournal = {Comparative Political Studies},
  volume = {54},
  number = {2},
  pages = {372--407},
  issn = {0010-4140, 1552-3829},
  doi = {10.1177/0010414020938081},
  url = {http://journals.sagepub.com/doi/10.1177/0010414020938081},
  urldate = {2024-03-14},
  abstract = {Populism has become a pervasive concept in political science research. However, a central and basic question remains unanswered: which European parties are more populist than others? Despite the increasing wealth of studies on populism in parties, we lack data that measures populism in political parties in a valid and precise manner, that recognizes that populism is constituted by multiple dimensions, and that ensures full coverage of all parties in Europe. In this article, we first appraise the weaknesses of existing approaches. Arguing that parties’ populism should be measured as a latent construct, we then advocate a new approach to operationalizing and measuring populism in political parties using expert surveys. Relying on the Populism and Political Parties Expert Survey spanning 250 political parties in 28 European countries, we show that populism is best measured in a multi-dimensional and continuous manner. We subsequently illustrate the advantages of our approach for empirical analysis in political science.},
  langid = {english}
}

@article{meijers2023,
  title = {It’s a Hoax! {{The}} Mediating Factors of Populist Climate Policy Opposition},
  author = {Meijers, Maurits J. and Van Drunen, Yaël and Jacobs, Kristof},
  date = {2023-11-10},
  journaltitle = {West European Politics},
  shortjournal = {West European Politics},
  volume = {46},
  number = {7},
  pages = {1288--1311},
  issn = {0140-2382, 1743-9655},
  doi = {10.1080/01402382.2022.2145447},
  url = {https://www.tandfonline.com/doi/full/10.1080/01402382.2022.2145447},
  urldate = {2024-09-05},
  langid = {english}
}

@incollection{meijers2023a,
  title = {Expert Surveys in Party Research},
  booktitle = {The {{Routledge Handbook}} of {{Political Parties}}},
  author = {Meijers, Maurits J. and Wiesehomeier, Nina},
  date = {2023},
  pages = {466--477},
  publisher = {Routledge},
  url = {https://www.taylorfrancis.com/chapters/edit/10.4324/9780429263859-48/expert-surveys-party-research-maurits-meijers-nina-wiesehomeier},
  urldate = {2025-07-05}
}

@article{mudde2004,
  title = {The Populist Zeitgeist},
  author = {Mudde, Cas},
  date = {2004},
  journaltitle = {Government and opposition},
  volume = {39},
  number = {4},
  pages = {541--563},
  publisher = {Cambridge University Press},
  url = {https://www.cambridge.org/core/journals/government-and-opposition/article/populistzeitgeist/2CD34F8B25C4FFF4F322316833DB94B7},
  urldate = {2024-03-14}
}

@book{mudde2012,
  title = {Populism in {{Europe}} and the {{Americas}}: {{Threat}} or Corrective for Democracy?},
  shorttitle = {Populism in {{Europe}} and the {{Americas}}},
  author = {Mudde, Cas and Kaltwasser, Cristóbal Rovira},
  date = {2012},
  publisher = {Cambridge University Press},
  url = {https://books.google.com/books?hl=nl&lr=&id=cRy2H220Gi4C&oi=fnd&pg=PR9&dq=mudde+kaltwasser+populism+democracy&ots=YRiDD5qf3I&sig=2Uyj1Bdu_ByHrrc1zCibvinO8QA},
  urldate = {2024-09-10}
}

@book{mudde2017,
  title = {An Ideational Approach},
  author = {Mudde, Cas},
  date = {2017},
  volume = {27},
  publisher = {Oxford University Press Oxford},
  url = {https://books.google.nl/books?hl=nl&lr=&id=X8Q9DwAAQBAJ&oi=fnd&pg=PA27&dq=ideational+approach+populism+mudde&ots=6OxsItOYXn&sig=T9z16caJ3xhkhow7UJecfmltLs0},
  urldate = {2024-08-22}
}

@book{mudde2019,
  title = {The Far Right Today},
  author = {Mudde, Cas},
  date = {2019},
  publisher = {John Wiley \& Sons},
  url = {https://books.google.com/books?hl=nl&lr=&id=aD25DwAAQBAJ&oi=fnd&pg=PT3&dq=mudde+the+far+right+today&ots=vYfGRiDQyJ&sig=h0v2tu5G1bBcHZE_z2IqmGPmh_I},
  urldate = {2024-01-22}
}

@book{muller2017,
  title = {What Is Populism?},
  author = {Müller, Jan-Werner},
  date = {2017},
  publisher = {Penguin UK},
  url = {https://books.google.nl/books?hl=nl&lr=&id=nv0tDwAAQBAJ&oi=fnd&pg=PT6&dq=jan+werner+muller+populism&ots=cIQEHz0zrb&sig=PsucjPBVRXIRPBfPHHYBdzVSfPo},
  urldate = {2024-08-22}
}

@article{norris2020,
  title = {Measuring Populism Worldwide},
  author = {Norris, Pippa},
  date = {2020-11},
  journaltitle = {Party Politics},
  shortjournal = {Party Politics},
  volume = {26},
  number = {6},
  pages = {697--717},
  issn = {1354-0688, 1460-3683},
  doi = {10.1177/1354068820927686},
  url = {http://journals.sagepub.com/doi/10.1177/1354068820927686},
  urldate = {2024-03-14},
  abstract = {Populism studies have rapidly burgeoned but systematic global empirical evidence about this phenomenon has lagged behind. How can party values be measured in consistent, valid, and reliable ways, facilitating identification of varieties of populism in countries around the world? To address this issue, part I outlines the conceptual framework. Part II describes the research design. The Global Party Survey (GPS) replicates previous expert surveys, expands coverage worldwide, and incorporates innovative scaled measures of populism. It draws upon estimates from 1861 experts and covers 1043 political parties in 163 countries (see www.GlobalPartySurvey.org ). Part III summarizes some key cross-national results. Part IV presents robustness tests which confirm that the new GPS estimates of ideological values and populist parties are consistently correlated with several previous measures. The conclusion in part V summarizes the main findings and considers the potential uses of the data set for understanding populism as a global phenomenon.},
  langid = {english}
}

@article{polk2017,
  title = {Explaining the Salience of Anti-Elitism and Reducing Political Corruption for Political Parties in {{Europe}} with the 2014 {{Chapel Hill Expert Survey}} Data},
  author = {Polk, Jonathan and Rovny, Jan and Bakker, Ryan and Edwards, Erica and Hooghe, Liesbet and Jolly, Seth and Koedam, Jelle and Kostelka, Filip and Marks, Gary and Schumacher, Gijs and Steenbergen, Marco and Vachudova, Milada and Zilovic, Marko},
  date = {2017-01},
  journaltitle = {Research \& Politics},
  shortjournal = {Research \& Politics},
  volume = {4},
  number = {1},
  pages = {205316801668691},
  issn = {2053-1680, 2053-1680},
  doi = {10.1177/2053168016686915},
  url = {http://journals.sagepub.com/doi/10.1177/2053168016686915},
  urldate = {2024-03-15},
  abstract = {This article addresses the variation of anti-corruption and anti-elite salience in party positioning across Europe. It demonstrates that while anti-corruption salience is primarily related to the (regional) context in which a party operates, anti-elite salience is primarily a function of party ideology. Extreme left and extreme conservative (TAN) parties are significantly more likely to emphasize anti-elite views. Through its use of the new 2014 Chapel Hill Expert Survey wave, this article also introduces the dataset.},
  langid = {english}
}

@article{rooduijn2011,
  title = {Measuring {{Populism}}: {{Comparing Two Methods}} of {{Content Analysis}}},
  shorttitle = {Measuring {{Populism}}},
  author = {Rooduijn, Matthijs and Pauwels, Teun},
  date = {2011-11},
  journaltitle = {West European Politics},
  shortjournal = {West European Politics},
  volume = {34},
  number = {6},
  pages = {1272--1283},
  issn = {0140-2382, 1743-9655},
  doi = {10.1080/01402382.2011.616665},
  url = {http://www.tandfonline.com/doi/abs/10.1080/01402382.2011.616665},
  urldate = {2025-06-29},
  langid = {english}
}

@article{rooduijn2015,
  title = {The {{Rise}} of the {{Populist Radical Right}} in {{Western Europe}}},
  author = {Rooduijn, Matthijs},
  date = {2015-06},
  journaltitle = {European View},
  shortjournal = {European View},
  volume = {14},
  number = {1},
  pages = {3--11},
  issn = {1781-6858, 1865-5831},
  doi = {10.1007/s12290-015-0347-5},
  url = {https://journals.sagepub.com/doi/10.1007/s12290-015-0347-5},
  urldate = {2024-10-10},
  abstract = {Populist radical right (PRR) parties are on the rise in Western Europe. Where do the electoral successes of these parties come from? First, it has been shown that the opening of borders has fuelled the divide between the ‘losers’ and ‘winners’ of globalisation. The ‘losers’ are individuals who feel threatened by international competition. They vote for PRR parties because they agree with their nativist, populist and Eurosceptic positions. Second, various social and political developments have facilitated the success of these parties. Some examples of these developments are increased electoral volatility, the ideological convergence of the mainstream parties, and increasing immigration and unemployment. Third, PRR parties themselves are, to a large extent, responsible for their own successes. Without their increasingly moderated messages and profiles, their often appealing external and internal leaders, and their well-institutionalised party organisations, their (long-term) successes would not have been possible. Most probably, the PRR party family will remain with us for a while.},
  langid = {english}
}

@article{rooduijn2019,
  title = {The {{PopuList}}: {{An}} Overview of Populist, Far Right, Far Left and {{Eurosceptic}} Parties in {{Europe}}},
  shorttitle = {The {{PopuList}}},
  author = {Rooduijn, Matthijs and Van Kessel, Stijn and Froio, Caterina and Pirro, Andrea and De Lange, Sarah and Halikiopoulou, Daphne and Lewis, Paul and Mudde, Cas and Taggart, Paul},
  date = {2019},
  url = {https://centaur.reading.ac.uk/89065/},
  urldate = {2024-03-14}
}

@article{samejima1969,
  title = {Estimation of Latent Ability Using a Response Pattern of Graded Scores},
  author = {Samejima, Fumiko},
  date = {1969},
  journaltitle = {Psychometrika},
  volume = {34},
  number = {S1},
  pages = {1--97},
  publisher = {Springer-Verlag},
  url = {https://www.cambridge.org/core/journals/psychometrika/article/estimation-of-latent-ability-using-a-response-pattern-of-graded-scores/87C005F61264FD8360992A8D0FC3FDE0},
  urldate = {2025-06-22}
}

@article{whitefield2007,
  title = {Do Expert Surveys Produce Consistent Estimates of Party Stances on {{European}} Integration? {{Comparing}} Expert Surveys in the Difficult Case of {{Central}} and {{Eastern Europe}}},
  shorttitle = {Do Expert Surveys Produce Consistent Estimates of Party Stances on {{European}} Integration?},
  author = {Whitefield, Stephen and Vachudova, Milada Anna and Steenbergen, Marco R. and Rohrschneider, Robert and Marks, Gary and Loveless, Matthew P. and Hooghe, Liesbet},
  date = {2007},
  journaltitle = {Electoral Studies},
  volume = {26},
  number = {1},
  pages = {50--61},
  publisher = {Elsevier},
  url = {https://www.sciencedirect.com/science/article/pii/S0261379406000369?casa_token=SMqI5ViqyOsAAAAA:BUmDEI4az6sTnFeG_z69WWppNuDnnSdnAKkfNjUC6j5Zyci3rvRIMRMpl-1LojiUZBtwJ8G_bLk},
  urldate = {2024-10-10}
}

@book{wolinetz2018,
  title = {Absorbing the Blow: {{Populist}} Parties and Their Impact on Parties and Party Systems},
  shorttitle = {Absorbing the Blow},
  author = {Wolinetz, Steven and Zaslove, Andrej},
  date = {2018},
  publisher = {ECPR press},
  url = {https://books.google.nl/books?hl=nl&lr=&id=XYYXEQAAQBAJ&oi=fnd&pg=PA1947&dq=wolinetz+and+zaslove&ots=D-WW4Vw4hi&sig=63wy8KkApwKwxkF3DxP19NrqIWQ},
  urldate = {2024-10-11}
}
